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1.
Antioxidants (Basel) ; 8(9)2019 Sep 01.
Article in English | MEDLINE | ID: mdl-31480581

ABSTRACT

Phenolics present in grapes have been explored as cosmeceutical principles, due to their antioxidant activity and ability to inhibit enzymes relevant for skin ageing. The winemaking process generates large amounts of waste, and the recovery of bioactive compounds from residues and their further incorporation in cosmetics represents a promising market opportunity for wine producers and may contribute to a sustainable development of the sector. The extracts obtained from grape marc and wine lees, using solid-liquid (SL) extraction with and without microwave (MW) pretreatment of the raw material, were characterized in terms of antioxidant activity through chemical (ORAC/HOSC/HORAC) and cell-based (keratinocytes-HaCaT; fibroblasts-HFF) assays. Furthermore, their inhibitory capacity towards specific enzymes involved in skin ageing (elastase; MMP-1; tyrosinase) was evaluated. The total phenolic and anthocyanin contents were determined by colorimetric assays, and HPLC-DAD-MS/MS was performed to identify the main compounds. The MW pretreatment prior to conventional SL extraction led to overall better outcomes. The red wine lees extracts presented the highest phenolic content (3 to 6-fold higher than grape marc extracts) and exhibited the highest antioxidant capacity, being also the most effective inhibitors of elastase, MMP-1 and tyrosinase. The results support that winemaking waste streams are valuable sources of natural ingredients with the potential for cosmeceutical applications.

2.
Food Chem ; 259: 188-195, 2018 Sep 01.
Article in English | MEDLINE | ID: mdl-29680043

ABSTRACT

Aging wine lees are water-wastes produced during the wine aging inside wood barrels that can be considered as alternative sources of bioactive compounds. Phenolic characterization and antioxidant activity (AA) measurements of wines lees solid-liquid extracts have been undertaken on a dry extract (DE) basis. Solvents with different polarities (water, methanol, ethanol, two hydroalcoholic mixtures and acetone) were used. Total phenolic (TPC) and total flavonoid contents (TFC) were determined. The mixture of 75:25(v/v) EtOH:H2O showed the highest values with 254 mgGAE/gDE and 146 mgCATE/gDE respectively. HORAC, HOSC and FRAP were used to determine the AA of the extracts being also highest for the mixture of 75:25(v/v) EtOH:H2O (4690 µmolCAE/gDE, 4527 µmolTE/gDE and 2197 µmolTE/gDE, respectively). For ORAC method, methanol extract showed the best value with 2771 µmolTE/gDE. Correlations between TPC, TFC, phenolic compounds and AA were determined. Most relevant compounds contributing to AA were identified using data from mass spectrometry, being mainly anthocyanins.


Subject(s)
Antioxidants/analysis , Wine/analysis , Anthocyanins/analysis , Anthocyanins/isolation & purification , Antioxidants/chemistry , Antioxidants/isolation & purification , Chromatography, High Pressure Liquid , Flavonoids/analysis , Flavonoids/isolation & purification , Phenols/analysis , Phenols/isolation & purification , Solid Phase Extraction , Tandem Mass Spectrometry , Time Factors
3.
J Antimicrob Chemother ; 72(1): 210-219, 2017 01.
Article in English | MEDLINE | ID: mdl-27659733

ABSTRACT

BACKGROUND: Routine HIV-1 antiretroviral drug resistance testing for patients failing NNRTI-based regimens is not recommended in resource-limited settings. Therefore, surveys are required to monitor resistance profiles in patients failing ART. METHODS: A cross-sectional survey was conducted amongst patients failing NNRTI-based regimens in the public sector throughout South Africa. Virological failure was defined as two consecutive HIV-1 viral load results >1000 RNA copies/mL. Pol sequences were obtained using RT-PCR and Sanger sequencing and submitted to Stanford HIVdb v7.0.1. RESULTS: A total of 788 sequences were available for analysis. Most patients failed a tenofovir-based NRTI backbone (74.4%) in combination with efavirenz (82.1%) after median treatment duration of 36 months. K103N (48.9%) and V106M (34.9%) were the most common NNRTI mutations. Only one-third of patients retained full susceptibility to second-generation NNRTIs such as etravirine (36.5%) and rilpivirine (27.3%). After M184V/I (82.7%), K65R was the most common NRTI mutation (45.8%). The prevalence of K65R increased to 57.5% in patients failing a tenofovir regimen without prior stavudine exposure. Cross-resistance to NRTIs was often observed, but did not seem to affect the predicted activity of zidovudine as 82.9% of patients remained fully susceptible to this drug. CONCLUSIONS: The introduction of tenofovir-based first-line regimens has dramatically increased the prevalence of K65R mutations in the HIV-1-infected South African population. However, most patients failing tenofovir-based regimens remained fully susceptible to zidovudine. Based on these data, there is currently no need to change either the recommended first- or second-line ART regimens in South Africa.


Subject(s)
Anti-Retroviral Agents/pharmacology , Drug Resistance, Viral , HIV Infections/drug therapy , HIV Infections/virology , HIV-1/drug effects , Adolescent , Adult , Aged , Aged, 80 and over , Anti-Retroviral Agents/therapeutic use , Cross-Sectional Studies , Female , Genotype , Genotyping Techniques , HIV-1/genetics , HIV-1/isolation & purification , Humans , Male , Middle Aged , Reverse Transcriptase Polymerase Chain Reaction , Sequence Analysis, DNA , South Africa , Treatment Failure , Viral Load , Young Adult , pol Gene Products, Human Immunodeficiency Virus/genetics
4.
J Infect Dis ; 214(12): 1826-1830, 2016 Dec 15.
Article in English | MEDLINE | ID: mdl-27923946

ABSTRACT

Limited data exist on human immunodeficiency virus type 1 (HIV-1) resistance in patients who are not responding to protease inhibitor (PI)-based regimens in resource-limited settings. This study assessed resistance profiles in adults across South Africa who were not responding to PI-based regimens. pol sequencing was undertaken and submitted to the Stanford HIV Drug Resistance Database. At least 1 major PI mutation was detected in 16.4% of 350 participants. A total of 53.4% showed intermediate resistance to darunavir/ritonavir, whereas high-level resistance was not observed. Only 5.2% and 32.8% of participants showed high-level and intermediate resistance to etravirine, respectively. Although the prevalence of major PI mutations was within previously reported ranges, most patients will likely experience virological suppression during receipt of currently available South African third-line regimens.


Subject(s)
Anti-Retroviral Agents/therapeutic use , Drug Resistance, Viral , HIV Infections/drug therapy , HIV Infections/virology , HIV Protease Inhibitors/therapeutic use , HIV-1/drug effects , Adolescent , Adult , Aged , Anti-Retroviral Agents/pharmacology , Cross-Sectional Studies , Gene Products, pol/genetics , HIV Protease Inhibitors/pharmacology , HIV-1/isolation & purification , Humans , Middle Aged , Mutation, Missense , Prevalence , Sequence Analysis, DNA , South Africa/epidemiology , Treatment Failure , Young Adult
5.
Bioprocess Biosyst Eng ; 39(12): 1825-1837, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27538771

ABSTRACT

Sophorolipids (SLs) were produced by Starmerella bombicola. The separation and purification of SLs are a complex process, since they are produced as a mixture of compounds with few structural differences. Solvent extraction is commonly used in downstream processing. In this work, an environmental friendly approach was developed for SLs recovery and purification, based on neutral polymeric sorbents, Amberlite XAD16NTM, XAD18TM, and XAD1600NTM. In batch microassays, key parameters of sorption/desorption process (e.g., contact time, temperature, sorbents, and SLs concentrations) were optimized for separation of acidic and lactonic SLs. Sorption equilibrium was reached after 2-3 h, for all the sorbents tested. Among them XAD1600NTM showed a higher sorption capacity (q max 230 mg g-1), a higher removal (≈100 %) of acidic and lactonic SLs [1 and 2.5 % (w/v)], and the best selectivity. Methanol, ethanol, and acetone were suitable for SLs elution. A selective desorption of SLs was attained with acetonitrile aqueous solutions (v/v): (1) 25 % led to 88.3 % of acidic SLs and (2) 55 % followed by methanol solution (100 %) led to 93.2 % of purified lactonic SLs. This achievement was particularly important regarding SLs potential therapeutic applications, since acidic and lactonic SLs show different biologic activities. In fact, acid SLs show higher virucidal and pro-inflammatory cytokine activity, while lactonic SLs show stronger spermicidal and anti-cancer activity.


Subject(s)
Antineoplastic Agents , Culture Media/chemistry , Lipids , Saccharomycetales/growth & development , Spermatocidal Agents , Antineoplastic Agents/chemistry , Antineoplastic Agents/isolation & purification , Lipids/biosynthesis , Lipids/chemistry , Lipids/isolation & purification , Spermatocidal Agents/chemistry , Spermatocidal Agents/isolation & purification
6.
J Carcinog Mutagen ; 7(2)2016 Apr.
Article in English | MEDLINE | ID: mdl-27335684

ABSTRACT

The identification of functionally relevant subpopulations of therapy-resistant cancer cells is a challenge. These cells, intrinsically resistant to conventional therapy, can cause recurrence. Evidence has suggested that therapy-resistant cancer cells are likely epithelial-mesenchymal transition (EMT) cells and/or stem-like cells called cancer stem cells (CSCs). EMT, a normal embryological process that converts epithelial cells into mesenchymal cells, is frequently activated during cancer development and progression. CSCs are a small subpopulation of cancer cells within a tumor mass that have the ability to self-renew and maintain tumor-initiating capacity by giving rise to heterogeneous lineages of cancer cells that comprise the whole tumor. Although the origin of CSCs and EMT cells remains to be fully explored, a growing body of evidence has indicated that the biology of EMT and CSCs is strongly linked. Doublecortin-like kinase 1 (DCLK1), a cancer stem cell marker, is functionally involved in maintaining cancer stemness and the process of EMT important for cancer initiation, cancer metastasis, and secondary tumor formation. Therefore, targeting these cells may provide new strategies to overcome tumor heterogeneity, therapeutic resistance, and cancer relapse. In this review, we will provide a potential mechanistic link between EMT induction and the emergence of CSCs for the origin and progression of cancer. We will highlight the functional activity of DCLK1 in supporting EMT and cancer cell self-renewal, which will lead us to a better understanding of DCLK1 expression in cancer development and progression, and help us to develop targeted therapies for effective cancer treatment.

7.
Food Chem ; 210: 558-65, 2016 Nov 01.
Article in English | MEDLINE | ID: mdl-27211682

ABSTRACT

Opuntia spp. fruits are considered as health promoting foods due to the diversity of bioactive molecules found in these fruits. The composition in organic acids, flavonols and betalains in the Opuntia ficus-indica juice from a region of Portugal was accomplished for the first time by liquid chromatography and tandem mass spectrometry using an electrospray ionization source operating in negative and positive mode. The methodology used allowed the detection of 44 compounds, from which 32 were identified. Isorhamnetin derivatives were the dominant flavonol glycosides. A total of 9 betalains including 6 betaxanthins and 3 betacyanin were also detected in the fruit juice samples and indicaxanthin, betanin and isobetanin were the major pigments. Phenolic acid and phenylpyruvic acid derivatives were also identified. To our knowledge, it is the first time derivative compounds from piscidic acid, phenolic compounds and betalains are characterized in cactus pear juice using a single LC-DAD-ESI-MS/MS method.


Subject(s)
Beverages/analysis , Chromatography, Liquid/methods , Fruit/chemistry , Opuntia/chemistry , Tandem Mass Spectrometry/methods , Betacyanins/analysis , Betaxanthins/analysis , Flavonols/analysis , Phenols/analysis , Plant Extracts/chemistry , Portugal , Pyridines/analysis , Quercetin/analogs & derivatives , Quercetin/analysis , Spectrometry, Mass, Electrospray Ionization
8.
Proc Nutr Soc ; 74(3): 268-81, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26186673

ABSTRACT

Olive oil (OO) is the primary source of fat in the Mediterranean diet and has been associated with longevity and a lower incidence of chronic diseases, particularly CHD. Cardioprotective effects of OO consumption have been widely related with improved lipoprotein profile, endothelial function and inflammation, linked to health claims of oleic acid and phenolic content of OO. With CVD being a leading cause of death worldwide, a review of the potential mechanisms underpinning the impact of OO in the prevention of disease is warranted. The current body of evidence relies on mechanistic studies involving animal and cell-based models, epidemiological studies of OO intake and risk factor, small- and large-scale human interventions, and the emerging use of novel biomarker techniques associated with disease risk. Although model systems are important for mechanistic research nutrition, methodologies and experimental designs with strong translational value are still lacking. The present review critically appraises the available evidence to date, with particular focus on emerging novel biomarkers for disease risk assessment. New perspectives on OO research are outlined, especially those with scope to clarify key mechanisms by which OO consumption exerts health benefits. The use of urinary proteomic biomarkers, as highly specific disease biomarkers, is highlighted towards a higher translational approach involving OO in nutritional recommendations.


Subject(s)
Biomarkers/urine , Cardiovascular Diseases/prevention & control , Olive Oil/therapeutic use , Animals , Humans , Models, Animal , Proteomics/methods , Risk Assessment/methods
9.
J Mol Recognit ; 28(3): 155-65, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25647712

ABSTRACT

Sophorolipids (SLs) are glycolipid biosurfactants, produced as a mixture of several compounds by some nonpathogenic yeast. In the current study, separation of individual SLs from mixtures with further evaluation of their surface properties and biologic activity on MDA-MB-321 breast cancer cell line were investigated. SLs were biosynthesized by Starmerella bombicola in a culture media supplemented with borage oil. A reverse-phase flash chromatography method with an automated system coupled with a prepacked cartridge was used to separate and purify the main SLs. Compositional analysis of SLs was performed by high-performance liquid chromatography with electrospray ionization mass spectrometry and tandem mass spectrometry. The following diacetylated lactonic SLs were isolated and purified: C18:0, C18:1, C18:2, and C18:3. The critical micelle concentration (CMC) and surface tension at CMC (γCMC ) of the purified SLs showed an increase with the number of double bonds. High cytotoxic effect against MDA-MB-231 cells was observed with C18:0 and C18:1 lactonic SLs. The cytotoxic effects of C18:3 lactonic SL on cancerous cells were for the first time studied. This cytotoxic effect was considerably higher than the promoted by acidic SLs; however, it induced a lower effect than the previously mentioned SLs, C18:0 and C18:1. To our knowledge, for the first time, C18:1 lactonic SL, in selected concentrations, proved to be able to inhibit MDA-MB-231 cell migration without compromising cell viability and to increase intracellular reactive oxygen species.


Subject(s)
Antineoplastic Agents/metabolism , Antineoplastic Agents/pharmacology , Breast Neoplasms/drug therapy , Glycolipids/biosynthesis , Glycolipids/pharmacology , Saccharomycetales/physiology , Cell Line, Tumor , Cell Movement/drug effects , Chromatography, Liquid/methods , Culture Media/chemistry , Female , Humans , Plant Oils/pharmacology , Reactive Oxygen Species/metabolism , Spectrometry, Mass, Electrospray Ionization , Tandem Mass Spectrometry , gamma-Linolenic Acid/pharmacology
10.
J Nutr Biochem ; 26(4): 360-8, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25620693

ABSTRACT

Virgin olive oil is the primary source of fat in the Mediterranean diet, and its beneficial health effects have been related with oleic acid and phenolic compounds content. Hydroxytyrosol, a typical virgin olive oil phenolic compound, has beneficial antioxidant and anti-inflammatory properties as previously reported. The aim of this study was to evaluate the effect of hydroxytyrosol-supplemented refined olive oil at 0.5 and 5 mg/kg in a rodent model of rheumatoid arthritis. Rheumatoid arthritis was induced by intradermic administration, in male Wistar rats, of Freund's adjuvant with collagen type II on days 1 and 21. Hydroxytyrosol-supplemented refined olive oils were administrated by gavage from day 23 until day 35. The treatment at 5-mg/kg dose significantly decreased paw edema (P<.01), histological damage, cyclooxygenase-2 and inducible nitric oxide synthase expression, and markedly reduced the degree of bone resorption, soft tissue swelling and osteophyte formation, improving articular function in treated animals. Acute inflammation, induced by carrageenan, was also evaluated for hydroxytyrosol-supplemented refined olive oils at 0.5 and 5 mg/kg. Both doses significantly reduced paw edema (P<.001). Our results suggest that the supplementation of refined olive oil with hydroxytyrosol may be advantageous in rheumatoid arthritis with significant impact not only on chronic inflammation but also on acute inflammatory processes.


Subject(s)
Arthritis, Rheumatoid/drug therapy , Dietary Supplements , Inflammation/drug therapy , Olive Oil/pharmacology , Phenylethyl Alcohol/analogs & derivatives , Acute Disease , Animals , Anti-Inflammatory Agents/pharmacology , Antioxidants/pharmacology , Cyclooxygenase 2/genetics , Cyclooxygenase 2/metabolism , Disease Models, Animal , Dose-Response Relationship, Drug , Down-Regulation , Male , Neutrophils/cytology , Neutrophils/drug effects , Neutrophils/metabolism , Nitric Oxide Synthase Type II/genetics , Nitric Oxide Synthase Type II/metabolism , Phenylethyl Alcohol/pharmacology , Rats , Rats, Wistar , Tumor Necrosis Factor-alpha/blood
11.
Food Chem ; 176: 455-64, 2015 Jun 01.
Article in English | MEDLINE | ID: mdl-25624256

ABSTRACT

The presence of mycotoxins in food samples has been widely studied as well as its impact in human health, however, information about its distribution in the environment is scarce. An analytical method comprising a solid phase extraction procedure followed by liquid chromatography tandem mass spectrometry analysis was implemented and validated for the trace analysis of mycotoxins in drinking bottled waters. Limits of quantification achieved for the method were between 0.2ngL(-1) for aflatoxins and ochratoxin, and 2.0ngL(-1) for fumonisins and neosolaniol. The method was applied to real samples. Aflatoxin B2 was the most frequently detected mycotoxin in water samples, with a maximum concentration of 0.48±0.05ngL(-1) followed by aflatoxin B1, aflatoxin G1 and ochratoxin A. The genera Cladosporium, Fusarium and Penicillium were the fungi more frequently detected. These results show that the consumption of these waters does not represent a toxicological risk for an adult.


Subject(s)
Chromatography, Liquid/methods , Drinking Water/microbiology , Mycotoxins/analysis , Solid Phase Extraction/methods , Tandem Mass Spectrometry/methods , Adult , Drinking Water/analysis , Humans
12.
Food Res Int ; 75: 61-70, 2015 Sep.
Article in English | MEDLINE | ID: mdl-28454973

ABSTRACT

Use of probiotic bacteria and consumes in large - in novel foods to provide beneficial health effects has attracted an increasing interest by the food industry and fermented olives are an excellent example of a new generation of those foods from plant origin so as to assure maximum viability by the time of ingestion during processing and storage of food products, as well as during transit through the gastrointestinal tract. Our study focused on production, characterization and assessment of efficacy of microencapsulation upon survival of probiotic strains and sensory properties of the final olive paste throughout refrigerated storage. Microencapsulation appears to be an effective technique for strain survival, depending on the operating temperature and experimental results on tolerance to gastrointestinal-like conditions, and ability to adhere to intestinal epithelium is thereby presented and discussed. The sensory panel rated all experienced matrices as good, including overall acceptance without significant preference between them. However, the success of microencapsulation was more limited when incorporated into olive paste. Free cells of Lactobacillus plantarum 33 proved able to survive in olive paste during storage at refrigerated temperatures.

13.
Food Funct ; 5(12): 3241-51, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25322288

ABSTRACT

Berries are an important dietary source of fibres, vitamins, minerals and some biologically active non-nutrients. A red raspberry fruit extract was characterized in terms of phenolic content and the anti-inflammatory properties and protective effects were evaluated in two experimental models of inflammation. The antioxidant potential of the extract, the cellular antioxidant activity and the effects over neutrophils' oxidative burst were also studied to provide a mechanistic insight for the anti-inflammatory effects observed. The extract was administered in a dose of 15 mg kg(-1), i.p. and significantly inhibited paw oedema formation in the rat. The same dose was administered via i.p. and p.o. routes in the collagen-induced arthritis model in the rat. The extract showed pharmacological activity and was able to significantly reduce the development of clinical signs of arthritis and markedly reduce the degree of bone resorption, soft tissue swelling and osteophyte formation, preventing articular destruction in treated animals.


Subject(s)
Anti-Inflammatory Agents/administration & dosage , Anti-Inflammatory Agents/chemistry , Arthritis/drug therapy , Edema/drug therapy , Plant Extracts/administration & dosage , Plant Extracts/chemistry , Rosaceae/chemistry , Animals , Antioxidants/administration & dosage , Antioxidants/chemistry , Arthritis/immunology , Disease Models, Animal , Drug Evaluation, Preclinical , Edema/immunology , Fruit/chemistry , Humans , Male , Neutrophils/drug effects , Neutrophils/metabolism , Oxidative Stress/drug effects , Rats , Rats, Wistar
14.
Food Funct ; 5(12): 3269-80, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25347222

ABSTRACT

In this work, Opuntia ficus indica juice was explored as a potential source of natural antioxidant and anti-inflammatory ingredients towards intestinal inflammation. An adsorption separation process was used to produce a natural flavonoid-rich concentrate (FRC) from Opuntia ficus-indica juice. The FRC effect (co- or pre-incubation) on induced-oxidative stress and induced-inflammation was evaluated in human Caco-2 cells. The main constituents identified and present in the extract are flavonoids (namely isorhamnetins and their derivatives such as isorhamnetin 3-O-rhamnose-rutinoside and isorhamnetin 3-O-rutinoside) and phenolic acids (such as ferulic, piscidic and eucomic acids). Our results showed that co-incubation of FRC with the stress-inducer attenuates radicals production in a much more significant manner than pre-incubation. These results suggest that FRC compounds which cannot pass the cell membrane freely (isorhamnetin derivatives) have an ability to inhibit the formation of H2O2-induced radicals in the surrounding environment of intestinal epithelial cells. The capacity of FRC (co-incubation) for suppressing (at the extracellular level) free radicals chain initiation or propagation reaction was probably related with a more pronounced reduction in protein oxidation. A similar response was observed in the inflammatory state, where a marked decrease in IL-8 secretion and blocked degradation of IκBα was achieved for FRC co-incubation. Simultaneously, treatment with FRC significantly reduces NO and TNF-α expression and modulates apparent permeability in Caco-2 cells. In these cases, no significant differences were found between pre- and co-incubation treatments suggesting that bioavailable phenolics, such as ferulic, eucomic and piscidic acids and isorhamnetin, act at the intracellular environment.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Antioxidants/pharmacology , Beverages/analysis , Flavonoids/pharmacology , Opuntia/chemistry , Plant Extracts/pharmacology , Anti-Inflammatory Agents/chemistry , Antioxidants/chemistry , Caco-2 Cells , Flavonoids/chemistry , Humans , Interleukin-8/genetics , Interleukin-8/immunology , Plant Extracts/chemistry , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/immunology
15.
Forensic Sci Int ; 244: 102-10, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25240621

ABSTRACT

Thirteen "legal highs" were purchased in different "smart shops" in the area of Lisbon, Portugal, during the month of February 2013. The samples were analyzed by a battery of analytical methods including Fourier transform infra-red (FTIR), gas chromatography coupled with mass spectrometry (GC-MS), proton nuclear magnetic resonance ((1)H NMR) and wavelength dispersive X-ray fluorescence (WD-XRF). Active ingredients were found either as single component or in mixtures in the different products. The cathinone derivative methedrone was present in three products; it is suspected to have a particular high toxicity and narrow therapeutic window linked with the methoxy group. A total of seven compounds were identified: 4-fluoromethcathinone, ethcathinone, buphedrone, methedrone, pentedrone, 3,4-dimethylmethcathinone and 4-methylethcathinone. Analytical profiles of all the samples were obtained and compared. Elemental composition of the products was obtained by XRF analysis. The inorganic profiles obtained contain useful information and can be used to distinguish and classify samples according to their origin.


Subject(s)
Alkaloids/analysis , Designer Drugs/chemistry , Illicit Drugs/chemistry , Psychotropic Drugs/analysis , Gas Chromatography-Mass Spectrometry , Humans , Magnetic Resonance Spectroscopy , Portugal , Spectrometry, X-Ray Emission , Spectroscopy, Fourier Transform Infrared
16.
J Am Soc Mass Spectrom ; 25(9): 1650-61, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25001380

ABSTRACT

The gas-phase behavior of 12 quinolon-4(1H)-imine derivatives with antiplasmodial activity was investigated using electrospray ionization tandem mass spectrometry together with collision induced dissociation and density functional theory (DFT) calculations. The most probable protonation site was predicted by calculating the proton affinity (PA) values for each possible protonation site and it was found to be the imine nitrogen for all compounds under study. Fragmentation pathways of the protonated molecules were proposed and the assignment of product ion structures was performed taking into account theoretical calculations. The nature of the quinoline substituent was found to influence the gas-phase behavior of the compounds under study. The data acquired allowed to bracket the proton affinity of the quinolin-4-imine scaffold, which can be a useful starting point to choose appropriate references for determining PA values of this scaffold.

17.
Int J Lab Hematol ; 36(6): 656-64, 2014 Dec.
Article in English | MEDLINE | ID: mdl-24666762

ABSTRACT

INTRODUCTION: Acute myeloid leukemia (AML) is a heterogeneous clonal disorder of hemopoietic progenitor cells diagnosed in individuals of any age, but with a median age of 67 years at presentation in adults. Assessment of the mutation status of nucleophosmin protein-1 (NPM1) and FMS-like tyrosine kinase 3 internal tandem duplication (FLT3-ITD) is essential for the prognosis, and treatment of AML. METHODS: A total of 160 de novo AML cases, both cytogenetically normal and abnormal, were analyzed for the presence of NPM1 and FLT3-ITD mutations, and the results assessed in conjunction with epidemiological, clinical, and laboratory findings. RESULTS: Nucleophosmin protein-1 mutations were found in 7.5%, while FLT3-ITD was present in 12% of these cases. Both of these were lower than expected. The median age at diagnosis of AML was 41 years, and for the FLT3-ITD only cases, median age was 33 years; these ages were younger than expected. CONCLUSION: The lower reported frequencies and younger median age at diagnosis of AML and these specific mutations may be contributed to by a number of factors including effects of race on age of presentation, inclusion of patients diagnosed with de novo AML only, and a generally younger median age of the South African population.


Subject(s)
Leukemia, Myeloid, Acute/genetics , Mutation Rate , Nuclear Proteins/genetics , fms-Like Tyrosine Kinase 3/genetics , Adolescent , Adult , Age Factors , Aged , Aged, 80 and over , Antineoplastic Agents/therapeutic use , Child , Cohort Studies , Female , Gene Expression , Humans , Leukemia, Myeloid, Acute/diagnosis , Leukemia, Myeloid, Acute/drug therapy , Leukemia, Myeloid, Acute/mortality , Male , Middle Aged , Nucleophosmin , Prognosis , Protein Structure, Tertiary , South Africa , Survival Analysis
18.
Toxicol Lett ; 224(1): 54-63, 2014 Jan 03.
Article in English | MEDLINE | ID: mdl-24459702

ABSTRACT

The identification of pyrrole derivatives in urine of rats exposed to 2,5-hexanedione (2,5-HD), was performed to select an adequate peripheral biomarker predictive of 2,5-HD neurotoxicity. Studies on molecular mechanism of 2,5-HD neurotoxicity have revealed that 2,5-hexanedione reacts with free amino groups of lysine in proteins forming primary pyrrole adducts, which may autoxidize and form pyrrole dimers, responsible for protein crosslinking in neurofilaments, or react with sulfhydryl groups of cysteine in peptides and proteins, forming secondary pyrrole adducts, which probably may inhibit the process responsible by 2,5-HD neurotoxicity. In this work, the analysis of excreted 2,5-HD and pyr-role derivatives in urine of rats i.p. treated with 3 doses of 2,5-HD (400 mg/kg bw/48 h) was performed using ESI-LC-MS/MS. Several pyrrole compounds were identified, namely dimethylpyrrole norleucine(DMPN), cysteine-pyrrole conjugate (DMPN NAC), glutathione-pyrrole conjugate (DMPN GSH) and 2,5-dimethylpyrrole (2,5-DMP). Additionally, free and total 2,5-HD, DMPN and DMPN NAC were quantified. The observed results suggest that DMPN is a sensitive and specific indicator of repeated exposure to 2,5-HD.


Subject(s)
Environmental Monitoring , Hexanes/toxicity , Hexanones/toxicity , Pyrroles/urine , Animals , Biomarkers/urine , Colorimetry , Hexanones/urine , Male , Rats , Rats, Wistar , Tandem Mass Spectrometry
19.
Sci Total Environ ; 487: 673-80, 2014 Jul 15.
Article in English | MEDLINE | ID: mdl-24200094

ABSTRACT

A method based on sample preparation by solid phase extraction and analysis by liquid chromatography and mass spectrometry was validated and used for simultaneous analysis of cocaine, benzoylecgonine and cotinine in samples collected at the major wastewater treatment plant in the city of Lisbon. The aim was to estimate the consumption of both cocaine and nicotine in this community and establish an index involving both drugs supported by the relevance of nicotine as a significant anthropogenic marker. The study was made on two different weekdays during a month in order to evaluate patterns of consumption outside weekends. Cocaine and nicotine ingestion levels were back-calculated and expressed as mass of pure drugs consumed per day and per 1000 inhabitants (mean: 0.604 g and 5.860 g respectively). Cocaine was also expressed on the basis of local drug purity levels (33.7%) with a corresponding increase on dose assessments, and community drug abuse profiles. The authors sustain that this approach should always be included in drug studies of this kind allowing a better drug abuse assessment. No significant different patterns of consumption were obtained during the working days studied with the exception of one case coincident with a national holiday that showed an increased typical profile found on other non-working day studies, namely weekends. A fairly significant relationship was found between nicotine and cocaine consumption that should be further evaluated in future studies. Pharmacokinetic considerations were made and proposed for cocaine assessment based on the impact on back calculations after common simultaneous consumption of cocaine and ethanol.


Subject(s)
Nicotine/analysis , Wastewater/chemistry , Water Pollutants, Chemical/analysis , Water Pollution, Chemical/statistics & numerical data , Chromatography, Liquid , Cocaine/analogs & derivatives , Cocaine/analysis , Environmental Monitoring/methods , Humans , Illicit Drugs/analysis , Solid Phase Extraction , Substance-Related Disorders/epidemiology , Tandem Mass Spectrometry , Wastewater/statistics & numerical data
20.
J Virol Methods ; 194(1-2): 300-7, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23994150

ABSTRACT

HIV-1 RNA viral load is the preferred tool to monitor virological failure during antiretroviral therapy (ART) exposure. Timely detection of virological failure can reduce the prevalence and complexity of HIV-1 drug resistance. This field evaluation further characterizes a two-step approach to identify virological failure, as a measure of ART adherence, and detect HIVDR mutations in the reverse transcriptase (RT) gene of HIV-1. Two hundred and forty-eight (248) samples were tested; 225 from South African HIV-1 participants enrolled in the PharmAccess African Studies to Evaluate Resistance (PASER) cohort, forty of which had paired dried blood spot (DBS) samples and 23 HIV-1 negative samples. A newly developed virological failure assay (ARTA-VFA) was used on all samples, and those with a viral load >5000 RNA copies/ml were genotyped with a shortened RT protocol to detect HIVDR (ARTA-HIVDR(ultralight)). The ARTA-VFA showed good precision and linearity as compared to a commercial reference assay (NucliSENS EasyQ v1.2, Roche) with an R(2) of 0.99. Accuracy studies illustrated standard deviations of <1 log RNA copies/ml for plasma and DBS ARTA-VFA results compared to the reference method. The ARTA-VFA's intended use was to deliver qualitative results either < or >5000 RNA copies/ml. No significant differences in the proportion of results < or > either the 5000 RNA copies/ml or 1000 RNA copies/ml cut-off were noted for plasma indicating either cut-off to be useful. Significant differences were noted in these proportions when DBS were used (P=0.0002), where a 5000 RNA copies/ml cut-off was deemed more appropriate. The sensitivity and specificity of the ARTA-VFA with plasma were 95% and 93% and 91% and 95% for DBS using a 5000 RNA copies/ml cut-off. The ARTA HIVDR(ultralight) assay was reliable for plasma and DBS samples with a viral load >5000 RNA copies/ml, with amplification and sequencing success rates of 91% and 92% respectively for plasma, and 95% and 80% respectively for DBS. HIVDR profiles for plasma and DBS were 100% concordant with the reference assay. This study evaluated a previously described combination of two assays potentially useful in assessing HIV-1 virological failure and resistance, showing good concordance with reference assays. These assays are simple to perform and are affordable, viable options to detect virological failures in certain resource limited settings. The assays' compatibility with DBS sampling extends the access of HIV-1 virological monitoring to more remote settings.


Subject(s)
Anti-Retroviral Agents/therapeutic use , Drug Resistance, Viral , HIV Infections/drug therapy , HIV Infections/virology , HIV-1/isolation & purification , Molecular Diagnostic Techniques/methods , Viral Load/methods , Anti-Retroviral Agents/pharmacology , HIV-1/drug effects , HIV-1/genetics , Humans , Microbial Sensitivity Tests/methods , Sensitivity and Specificity , South Africa , Treatment Failure
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